The present invention relates generally to baling machines, and more particularly to a method and apparatus for fine adjustment of moving part sequences in balers.
A big square baler has a knotter shaft driven by a main gear, a needle bar that is driven by at least one knotter shaft, and a feeding mechanism for the baling material that is driven by the main gear.
To guarantee problem-free operation and to avoid damage to the functional components of big square balers, the moving part sequences between the feeding mechanism, the baling ram, the needle bar and the knotter must be precisely coordinated. Problem-free operation necessitates an adjustment of moving elements during the machine assembly process and following certain operational intervals. With big square balers the synchronized actions can be adjusted by placing certain markers on the individual drive elements or on certain components. In certain positions, these markers have to take a pre-determined orientation relative to one another. The adjustment guide markers provide a means to coordinate the motion sequences of the individual functional elements. However, this method may not be sufficient in all cases to ensure optimum operability without further additional fine-adjustment mechanisms, especially when experiencing signs of tolerance and wear. In particular, knotter shafts driven via a roller chain, require corrective adjustments of the driving means after lengthy use due to wear.
For example, a fine adjustment between the baler ram and the needle bar is well known from DE-37 30 732 A1, where the roller chain tension is adjusted and the driven sprocket on the knotter shaft is pivoted, thereby changing the position of the needle tip towards the baler ram. However, such adjustment devices require additional elaboration. Furthermore, roller chain drives do not guarantee precise transmission ratios. While other well-known, higher-quality transmission means such as sprockets, gear boxes and universal drive shafts allow a more precise coordination of the moving elements relative to each other, they also require elaborate fine-adjustment devices.